Schreger pattern

A polished cross-sections of elephant and mammoth ivory dentine will display uniquely characteristic Schreger lines. Schreger lines is a system of crossing lines that could be seem in all cross sections of a piece of ivory from the tusks of the mammalian order proboscidea, which includes elephants and mammoths. Mammoth lines are crossing at less than 100 degrees, while elephant ivory schreger lines will cross at an angle larger than 100 degrees. Mammoth has been extinct for more than 10,000 years but their tusks have been possible to use for decorative carvings when found well preserved.